[b]Proposition 2: [i][It is possible] to place at a given point a straight line equal to a given straight line.[/i][/b]

1. Below you will find Euclid's instruction to construct a line segment through a point equal in length to a given line segment. Using the GeoGebra applet, follow these instruction. [br][br]Let A be the given point, and BC the given straight line.[br]From point A to point B let the straight line AB be joined; [br]and on it let the equilateral triangle DAB be constructed (use [icon]/images/ggb/toolbar/mode_regularpolygon.png[/icon] tool)[br]Let the straight lines AE, BF be produced in a straight line with DA, DB (in o[sub][/sub]ther words, use the ray tool [icon]/images/ggb/toolbar/mode_ray.png[/icon] to extend lines DA and DB to create lines AE and BF by creating new points E and F on DA and DB respectively);[br]Create circle with center B and distance BC (where G is the intersection of the circle with line BF);[br]and again, create circle with center D and distance DG (where H is the intersection of the circle with line AE);